Method of producing printing-surfaces.



ED STATES @FFEQE;

OSCAR ronns'rnn, on NEW YonK, n. Y., nssrsnon or ONE-HALF 'ro ARTHUR sesame, on NEW YORK, N. Y.

METHOD OF PRODUCING PRINTING-SURFACES.

No Drawing.

To all whom it may concern:

Be it known that I, OSCAR Fonns'rim, a citizen of the United States, residing at New York city, in the county of New York and State of New York, have invented certain new and useful Improvements i Methods of Producing Printing-Surfaces, of which the following is a specification.

My invention relates to methods of producing grain screen plates for reproducing pictures by the well known lithographic and plate printin methods and m object is the production 0 glass plate, cel uloid, or any other suitable material negatives or positives for producing printing surfaces on stone, zinc, aluminum, copper or other suitable base, and also for producing intaglio plates having an irregular screen grain the texture of which is under the full control of the operator.

The negativesor positives produced by my method have an irregular, fine, open and sharp surface grain 1producing printing surfaces that meet al the requirements for steam press work of a high degree of excellence and are capable of producing highly artistic results.

The grain is absolutely under the control of the operator and any desired degree of fineness of the grain can be produced according to the requirements of the subject to be reproduced.

I will describe my method as applied to the production of glass negatives or positives embodying the rain screen as that is the base usually emp oyed in practice.

In preparing my grain screen plate I first prepare the following solutions (A) Albumen 10 'gms.

Water -1.-- 80 cc.

(B) Ammonium chlorid 10 gms.

Water 100 cc.

(0) Ammonium bichromate 1 gm.

Water ..1 30 cc.

and mix' the three solutions in the following proportions cc. of A, ,cc. of B and 15 cc. of C, which I call solution No. 1. This solution No. i is poured over a thoroughly clean glass plate at a temperature of about 16 C. and the surplus solution drained off after which the plate is dried in the dark.

Specification of Letters Patent.

Patented May '7, 1918.

Application filed March as, 1917. Serial nous-1,551.

When dried the coated plate is exposed, face down, on a non-actinic surface to ditiused daylight for a short time.

I I nerf' prepare the following solution which i call N o. 2:

(A) Soft gelatin 50 gms.

Water 500 cc.

(B) Potassium bichromate 10 gms. Ammonium bichromate -5 gms.

10 gms. is the normal amount of sodium sulfite used and is decreased to a minimum of 5 gms. in event of extreme humidity.

A is dissolved at a temperature of C. and B is added while stirring. C isfinally well stirred into the mixture until homogeneous after which it is freed from bubbles- The sub-coated glass plate is then heated to about 50 C. and solution No. 2, at the same temperature,is poured over the coated side and subjected to a temperature of about 65 C. for about two hours in a. level position.

When cooled the prepared plate is exposed under a negative or positive after which it is immersed in luke warm water until the grain is visible. It is then washed in ll water until it attains a silver gray color. It may then be hardened in any suitable hardening bath if desired.

The plate is again washed if the hardening bath has been used and the surplus moisture removed until the surface is sticky or adhesive.

Finely powdered opaque or non-actinic material which is unaffected by the etching fluid later employed, such as bronze powder, is dusted over the sticky surface and the dusted plate permitted to dry. The plate is next placed in an etching fluid, such as a highly diluted solution of hydrochloric acid in water, and very carefully developed by gently rubbing with cotton. The non-actinic powder must remain in the microscopic depressions in the surface of the film and development should continue until the finest white dots appear in the shadows and the finest black dots appear in the high lights for a negative plate and the reverse for a posiiive plate.

After development. by aching the plate is washed, dried and varnished ii clesirecl.

The grain screen plate is then ready to be used in the regular phoio-lilhogi'apliic processes of producing printing surfaces.

The prepared, sensitizeci plate may be photographed upon 'inlhe camera if clesirecl islead of being printecl uncles a negative or positive.

The finally developed plate may be manipula Pl with transfer ink anal a leather roller I053 the purpose of producing transfer impressions.

drain screens may be prepared by my method for use either in the camera or printing frame in the manner Well known to photo-engravers but screens so used never produce as fine results as the preferred zneihocls above descrioecl'hy the practice of which ihe screen is incorporated in she posifiive or negative itself.

1 claim:--

1, The method of producing grain screen plates hai ing a fine sharp, irregular grain comprising coating a plate With a hichroinatecl elatin containing grain producing material, exposing it to the action of light, i'eniov the unaltered laiin rendering gelatin surface adhesive, elusiing "the on non-actinie powder c. l

ing the owder adheiing n the in the gelatin coating.

52. The method of producing grain screen plates having a fine, sharp, irregular grain oomprising coating a glass plate wiehloichromatecl albumen, exposing the loan thereof to the action of light, removing the unaffected albumen, coating the albuminized plate with lJlCill0111i1tCl gelatin containing grain producing material, exposing the double-coated plate to the action of light, removing the. unafiected gelatin, rendering the surface adhesive, dusting thereon a non actinio owclei and finally removing the powder a hering to the high points in. the gelatin coatin 7 The method of producing grain screen plates consisting in coating a plate with loichromateil gelatin containing a grain pro clucing substance exposing it to the action of light, removing the unafi'ected gelatin, hardening the remaining gelatin, rendering the surface adhesive, dusting thereon a non actinic powder and finally removing the powder adhering to the high points the gelatin coating.

7 In testimony whereof l have refined signature in the presence of two witnesses: @SCAR Witnesses RonmT B. llinL-Gonn, Renee 

